How To Jailbreak iPhone 3G/3GS Firmware 3.1.2 Using blackra1n RC3?

In order to jailbreak your iPhone with 3.1.2 firmware you need blackra1n, a two-in-one jailbreaking and unlocking tool. The latest version of blackra1n, RC3 can jailbreak iPhone2G, 3G as well as 3GS running on baseband 05.11.07. Here are the steps to use blackra1n (created by geohot) to jailbreak  your iPhone (2G/3G/3GS) or iPod Touch (1G/2G/3G) with firmware 3.1.2:

Requirements:

Download and install the latest version of iTunes if you don’t have it already on your PC.

Your iPhone should be updated to  iPhone OS 3.1.2.

1. Download blackra1n RC3 for Windows or Mac.

2. Connect your iPhone or iPod Touch to your computer

2. Run the downloaded blackra1n application. In case you are running the application on Windows Vista or Windows 7, run the program in Windows XP compatibility mode. You can enable this mode from the ‘Properties’ tab.

3. Click on ‘make it ra1n’. This will place your device in the recovery mode. The recovery mode screen is replaced with a picture of geohot, the author of blackra1n.

4. blackra1n will show a message ‘done, wait for reboot’. Wait for your phone to automatically reboot.

5. After rebooting, your iPhone will be jailbroken. You should now find blackra1n in the list of applications running on your iPhone. The blackra1n icon appears on the Springboard.

6. Run this blackra1n app on your iPhone after making sure you have an internet connection. The app presents you with a list of packages, including Cydia, Rock and blacksn0w which is the unlock software given by geohot.

7. Select the package(s) you want to install and blackra1n will download and install them. This will complete the jailbreak process for your iPhone or iPod touch.

8. For example if you chose to install Cydia, you will find Cydia on your iPhone’s Springboard after the above process is complete.

9. Reboot your device to get a fully jailbroken iPhone running on firmware 3.1.2. You can uninstall Blackra1n any time you want to from the Springboard.